PULASKI COUNTY, Mo. (June 30, 2010) — Spiders, Yuk! Most of us think about those horror movies with awful tarantulas crawling all over our bodies.

A lot of people have been telling me they are seeing numerous brown recluse spiders this year. I don’t know if all the spiders they are seeing are brown recluse or not, but almost all of the 30,000 species of spiders are venomous. However, the fangs of most species are too short or too fragile to penetrate the humans’ skin. Only a few spider venoms have been studied in detail.

The brown recluse spider is very common in the southern and Midwestern United States but can be seen in a much wider geographic area. These spiders seem to be right at home in abandoned buildings, sheds, and workshops.

The brown recluse is not a large spider at all, only a half-inch long and a quarter-inch wide, but it can give people a nasty bite. The spider is usually brown or tan and has a violin-shaped bad of a darker color that extends backwards from its eyes, thus its other names of “fiddleback” or “violin” spider. The scientific name is Loxosceles.

The bite of a brown recluse spider may not even be noticed at first. Several hours might pass before the local reaction is felt. The reaction that occurs may be that of a painful, reddened area with overlying blister formation and a white surrounding area of ischemia, which means that the tissue is deprived of bloodflow. During the next few days or longer, the area turns dark and becomes deeply ulcerated. It is usually at this point that the bite victim seeks medical care. Sometimes there is a systemic reaction consisting of weakness, nausea, vomiting, fever, chills, rash, and anxiety. There are some extreme cases of seizures, internal blood clotting failure, and renal failure resulting in death.

In the pre-hospital setting, the treatment for a brown recluse spider bite is mostly general supportive care. If the patient is systemically sick, the paramedics will start oxygen, begin an IV of normal saline, and will monitor the patient’s EKG and vital signs.

In the hospital, the physician may cleanse the wound, give a tetanus prophylaxis, and keep the patient under observation. The doctor might use some ice and extremity elevation to reduce the pain. When ulceration occurs, the doctor might consider various medications and surgical excision, if necessary.